Bovine colostrum is a unique secretion of the mammary gland which is produced during the first few days of lactation. This secretion differs a great deal from normal milk. All of its components are not known, however it has been recognized to be very rich in immunoglobulins for the newborn. Intake of colostrum is essential during the first 24 hours of a calf's life. Due to the structure of the bovine placenta, transplacental transfer of immunoglobulins which confers passive immunity in most mammals is negligible. In this species nearly all passive transfer occurs by way of colostrum which is absorbed by the calf. The immunological components of colostrum include specific immunoglobulins IgG, IgM, IgA which convey passive immunity to the newborn. Peak serum immunoglobulin levels in colostrum are normally reached between 12 and 24 hours after birth. The calves intestinal permeability to these proteins is generally highest immediately after birth and declines after about six hours.
After this "window of opportunity" there is gut closure and further immunoglobulin absorption through the gut becomes negligible. Consequently calves over twenty-four hours old are essentially incapable of absorbing necessary immunoglobulins for passive transfer of immunity. This difficulty is termed failure of passive transfer (FPT) and is characterized by insufficient numbers of immunoglobulins present in the bloodstream prior to gut closure.
This failure prevents the protection of the newborn from most pathogens encountered until the animal's own immune system is exposed to various disease antigens and produces its own immunoglobulins to these diseases.
While the role of colostrum in conferring passive immunity during the critical first hours of a neonate's life has long been appreciated, virtually no recognition to date has been made of colostrum's potential benefits after gut closure.
Consequently, methods of assisting the health of calves over 24 hours old or even adults have concentrated on purified traditional milk and conventional thinking has been the colostrum would serve no useful purpose after gut closure. As a result purified traditional milk and other methods such as administration of the highly controversial bovine growth hormone have been explored. While bovine growth hormone, when administered, has been shown to increase milk production, milk quality has suffered. There is also a psychological problem in that many consumers refuse milk from so treated dairy cows.
Still other methods have included use of genetic markers to improve overall health and performance of cows. Thus a particular genotype may be screened for aid in selection of dairy cows which possess underlying genetic criteria which will result in a desirable phenotype.
Despite all of these developments, many expensive and involving controversial technology, no one to date has recognized the potential use of all-natural colostrum for improvement of calf and adult cow health and performance by consistent and regular dosing after gut closure.
While the presence and necessity of specific immunoglobulins in colostrum has long been appreciated, little or no attention to date has been paid to the plethora of additional non specific proteins found in colostrum. Current research has shown that colostrum contains several nonspecific proteins, for example transferin and lactoferin which bind iron, an essential growth factor for most aerobic bacteria. Enzymes such as lysozyme, xanthine oxidase and lactoperoxidase, which have been shown to have antimicrobial activity, particularly in the gut are present. Insulin-like growth promoting factors which increase uptake of glucose and amino acids by cells in the body, are present. Further, colostrum contains several additional components like conglutinin and the basic proteins .beta.-lysin and ubiquitin, although scientific knowledge of the function of those is limited. These important characteristics of colostrum, it has now been discovered, can be used in treatments after gut closure.
Thus it is an object of the present invention to make use of colostrum as an aid to improve overall health and performance of calves and cows, particularly after gut closure.
It is yet another object of the present invention to prepare a purified injectable product derived from colostrum which includes these proteins and is useful after infancy, recognizing the continuing benefits of these proteins in even adult cows.
Further there exists a great need for a method of treating failure of passive immunity after gut closure and an object of the invention is to provide a treatment of FPT by injection of purified colostrum immunoglobulins and nonspecific proteins directly into the calf, with a high efficacy.
Another object of the invention is to provide a method of improving weight gain by calves by use of a dietary supplement of proteins derived from colostrum.
Yet another objective is to increase daily milk production in adult cows by use of a dietary supplement of proteins derived from colostrum. The method of accomplishing these and other objectives will become apparent from the following description of the invention.